Given the billions of food items that are packaged, purchased and consumed every day in the U.S., let alone the world, it is remarkable how few of them are contaminated. Yet since the terrorist attacks of September 11, 2001, “food defense” experts have grown increasingly worried that extremists might try to poison the food supply, either to kill people or to cripple the economy by undermining public confidence. At the same time, production of edible products is becoming ever more centralized, speeding the spread of natural contaminants, or those introduced purposely, from farms or processing plants to dinner tables everywhere. Mounting imports pose yet another rising risk, as recent restrictions on Chinese seafood containing drugs and pesticides attest.

Can the tainting of what we eat be prevented? And if toxins or pathogens do slip into the supply chain, can they be quickly detected to limit their harm to consumers? Tighter production procedures can go a long way toward protecting the public, and if they fail, smarter monitoring technologies can at least limit injury.